Phonograph stylus mount



April 8, 1947. R A aCDONA D 2,418,591

PHONOGRAPH STYLUS MOUNT Filed July 24, 1943 INVENTOR Emwaep 2 Mn: 004/440 @ZZAMV ATTORNEYS.

Patented Apr. 8, 1947 PHONOGRAPH STYLUS MOUNT Richard A. MacDonald, Oshkosh, Wis, assignor to Flexograph, Inc.

Application July 24, 1943, Serial No. 495,976 (01. 274-38) 6 Claims.

This invention relates to improvements in phonograph stylus mounts.

As the tone arm of a phonograph moves across the record, a needle or stylus fixed thereon is not maintained tangent to the record groove but is first angularly displaced toward one side and then toward the other. Consequently, the point of the stylus does not bear a fixed relationship to the sound track and, moreover, the stylus point wears unevenly, both of which factors are undesirable in that they unfavorably influence the quality of the sound reproduced and tend to cause excessive record wear.

It is a primary object of the present invention to provide simple means which may be employed either in a specially built phonograph pickup or incorporated in existing equipment to permit and require theneedle to be at all times substantially tangent to the record groove irrespective of the position of the tone arm in its travel across the record.

1 At the same time, it is an object of the invention to accomplish this result without precluding the use of my improvement in automatic phonographs. In such phonographs, when the reproduction of a new record commences, the needle is automatically deposited on the record near its extreme outer periphery. Any substantial lateral displacement of the needle from its proper relationship to the tone arm at this point may result in the non-engagement of the needle with the first groove of the record. In accordance with the present invention, I provide means for use when needed to restrict relative movement between the needle and the tone arm so that the needle will surely fall within the permissible range of movement to assure its engagement in the beginning of the record groove.

Other objects of the invention will be apparent to those skilled in the art from the following disclosure thereof.

In the drawings:

Fig. 1 is a view partially in side elevation and partially in section showing an improved needle and mounting embodying the invention.

Fig. 2 is an enlarged detail view in cross section on the line 2-2 of Fig. 1.

Fig. 3 is a view similar to Fig. 1 showing a modified embodiment of the invention.

Fig. 4 is a view similar to Fig. 1 showing a further modified embodiment of the invention.

Fig. 5 is a view in side elevation of a further modified embodiment of the invention, this view showing how any of the various forms of the invention are applicable to a conventional ton arm.

Like parts are identified by the same reference characters throughout the several views.

It will be understood that the invention herein disclosed is applicable to any phonograph whether the reproduction is mechanical or electrical and regardless of the nature of the needle or stylus point. It is also applicable regardless of whether the sound track in the record groove is vertical or lateral. Emphasis is placed on this fact because it required experimentation to dem-:

onstrate that the invention would operate on a modern, lateral type sound track notwithstanding the fact that the invention contemplates freedom of limited lateral movement of the stylus point with respect to the reproducer.

In all forms of the invention, the stylus point 6 is offset in some. manner from an axis upon which such point is mounted for swiveled movement. In the construction shown in Fig. 1, the stylus itself has an offset at 7 between the point and the stylus shank 8, which is swiveled in a mounting sleeve 9 for approximately 22 degrees of movement afforded by the pin it which projects from the stylus shank and operates in a slot H in sleeve 9. This pin secures the stylus against loss from the sleeve or mount while, at the same time, limiting the swiveling movement of the stylus to a range such that the stylus will be assured of engagement with the beginning of the record groove when the assembly is used in an automatic phonograph.

It will, of course, be understood that various mechanical expedients may be employed as desired to limit the range of relative swiveling movement.

The sleeve or mount 9 is receivable into the stylus socket of any phonograph reproducer, corresponding in diameter to the cross section of any conventional stylus or needle. When so mounted, the movement of the record beneath the stylus point in the normal direction (which is from right to left, as viewed in Fig. 1) will automatically maintain the offset portion 1 substantially tangent to the record groove at all times, regardless of the position of the tone arm. Thus, in every position, the stylus point 6 will maintain a constant relationship to the record groove, thereby avoiding unequal wear on the stylus point and damage to the groove.

In the construction shown in Fig. 3, the stylus point is offset at 'Hlfrom the shank 8B and the shank is journaled or swiveled in a sleeve for the purposes above noted, The principal 3 difference between the device shown in Fig. 3 and that shown in Fig. 1 lies in the fact that the pin I is dispensed with and the end l2 of the sleeve 90 is spun into a groove l3 in the stylus shank 80 as a means of maintaining the parts in assembly for unitary handling. It is assumed that in the Fig. 3 device, it will not be necessary to limit the oscillation of the stylus in its mount. Should such limiting be necessary, any desired means engageable between the respective parts may be employed for the purpose.

In the construction shown in Fig. 4, the stylus h 6| has an offset at H connecting itwith a shank 8| which, in this instance, is tubular. The mount 9|, in this instance, comprises aspindle receivable into the conventional needle socket and reduced to provide a shoulder at M and a head at ,I with an intervening bearing section it upon which the tubular shank 8| of the stylus is swiveled.

Fig. 5 shows a tone arm l9 with a reproducer head 20 which, as aforesaid, may be either of the mechanical or electricaltype. From the head}!!! projects the conventional needle-carrier 2i socketed to. receive a needle andprovided with a retraining set screw at 22, In lieu of the conventional needle, I propose to substitute an adapter comprising any one of; my mounting devices such, for'eXample, as the. sleeve 9, in which is swiveled the shank which carries; an offsetat E2 on which is,a substituted needle-receiving socket 23 having a set-screw 24}to .hold-:aconventional needle or stylus 62. Where the adapting device of Fig. 5 is employed, any standard. existing needle may be inserted in the adapter andthe; adapter thereupon provides aswiveled mounting for such needle receivable in the carrier-of any-reproducer.

All of the several devices disclosed comprise a mount of some character, a: shank swiveled in some manner for, oscillatory movement with respect to the mount, and anofiset arm supporting the-stylus point in a position so displaced from the ,axis upon which the assembly; swivels that, as the tone arm-moves across a record, the stylus is caused to assume a trailing position inwhich a line drawn horizontally from the pointto the projected axisupon which the stylus swivelsis tangential to the record groove, or substantially so. Wherever desired, it ispossible to provide for interaction bet-ween the parts having the swiveled relation to limit theextent of swiveling movement; In ordinary practice, this movement may advantageously belimitedto approximately 22 .degrees which will preclude the stylus from becoming too widely displaced fromits' desired position while; at the samev time, allowing itisuffi i cient freedom of movement so that itmayop erate in tangential relationship to the record groovethroughoutits travel in .the course of reproduction.

I claim:

1. In a devicefor reproduction from a laterally cut record, the combination with=a sleeve of such length and-,diameter as to -;be receivable in-, a

stylus socket of a reproducer, of a carrier comprising a shank freely swiveled in the sleeve and provided with an offset portion comprising a stylus carrying member, means limiting the range of swiveling oscillation of the shank in the sleeve, said shank being freely oscillatable within said range whereby said ofiset portion may assume a trailing, swivelling position with respect to a. record; groove traversed'bysaid socket.

2; In adevice for reproducing'laterally cut records, the combination with a sleeve of such length and diameter as to be receivable in the stylus socket of a reproducer, of a carrier comprising a shank swiveled in the sleeve and providedbelow the sleeve with a shouldered and offset stylus carrying portion, said sleeve and shank having means directly engageable for limiting the oscillation of the shank within the sleeve.

3. The device of claim 2 in which the shank has .a laterally projectingpinand; the sleeve. an

arcuate slot with the marginsiof which. said pin.

is .engageable, said pin and margins comprising the means aforesaid, for limiting the .oscillation of the shank within the sleeve:

4. In a devicefor reproduction from laterally cut records, the combination with astylus point having a laterally offset portion. and provided with ashank projectingrfrom saidportion in oiisetrelation to thepoint,- of:a,s1eeve within whichsaid shank is swiveledfor oscillation, said sleeve and shank being provided ,with interlocked, means limiting their relativedisplacement, the.

sleeve being of such length and diameter as to be receivable in the stylus.:sockett of a reproducer for laterally. cut; records.

5-. 'Ihedeviceof claim- 4;in which'saidinteblocking; means comprises ;a pinprojecting laterally from. the shank, the. sleeve having an arcuateslot; through which said pin projects;

6. The device of claim 4 in which said inter-R locking; means comprises .a grooveextending circumferentially of the shank; said sleeve havin an oiisetgportion engaged-pin said groove.

' RICHARD A; MACDONALD.

REFERENCES CITED.-

The following references-are of record in the file of this patent:

UNITED STATES PATENTS British, .Mar. 11, 1909 

